package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.Voucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.hmdp.utils.RedisIdWorker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.connection.stream.*;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.time.Duration;
import java.time.LocalDateTime;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

@Service
@Slf4j
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {
    @Resource
    private ISeckillVoucherService seckillVoucherService;

    @Resource
    private RedisIdWorker redisIdWorker;

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    @Resource
    private RedissonClient redissonClient;


    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;


    private final ExecutorService SECKILL_ORDER_EXECUTOR =Executors.newSingleThreadExecutor();



    @PostConstruct
    private void init(){
        SECKILL_ORDER_EXECUTOR.submit(new VoucherOrderHandler());
    }

    private final BlockingQueue<VoucherOrder> orderTasks = new ArrayBlockingQueue<>(1024*1024);
    private class VoucherOrderHandler implements Runnable{
        String queueName = "stream.orders";
        @Override
        public void run() {
//            与之后的课程冲突，先注释掉
//            while(true){
//                try {
//                    List<MapRecord<String, Object, Object>> read = stringRedisTemplate.opsForStream().read(
//                            Consumer.from("g1", "c1"),
//                            StreamReadOptions.empty().block(Duration.ofSeconds(2)),
//                            StreamOffset.create(queueName, ReadOffset.lastConsumed())
//                    );
//                    if(read==null||read.isEmpty()){
//                        continue;
//                    }
//                    MapRecord<String, Object, Object> entries = read.get(0);
//                    Map<Object, Object> value = entries.getValue();
//                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(value, new VoucherOrder(), true);
//                    handleVoucherOrder(voucherOrder);
//                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",entries.getId());
//                } catch (Exception e) {
//                    log.error("处理订单异常",e);
//                }
//            }
        }

        private void handlePendingList() throws InterruptedException {
            while(true){
                try {
                    List<MapRecord<String, Object, Object>> read = stringRedisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1),
                            StreamOffset.create(queueName, ReadOffset.from("0"))
                    );
                    if(read==null||read.isEmpty()){
                        break;
                    }
                    MapRecord<String, Object, Object> entries = read.get(0);
                    Map<Object, Object> value = entries.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(value, new VoucherOrder(), true);
                    handleVoucherOrder(voucherOrder);
                    stringRedisTemplate.opsForStream().acknowledge(queueName,"g1",entries.getId());
                } catch (Exception e) {
                    log.error("处理pending-List异常",e);
                }
            }
        }
    }

    private void handleVoucherOrder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        RLock lock = redissonClient.getLock("lock:order:" + userId);
        boolean isLock = lock.tryLock();
        if (!isLock) {
            log.error("不能重复下单");
            return;
        }
        try{
            proxy.createVoucherOrder(voucherOrder);
        }finally {
            lock.unlock();
        }

    }

    static{
        SECKILL_SCRIPT=new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }

    private IVoucherOrderService proxy=null;
    @Override
    @Transactional
    public Result seckillVoucher(Long voucherId) {
        Long id = UserHolder.getUser().getId();
        long order = redisIdWorker.nextId("order");
        Long result = stringRedisTemplate.execute(SECKILL_SCRIPT, Collections.emptyList(), voucherId.toString(), id.toString(),String.valueOf(order));
        int r = result.intValue();
        if (r!=0){
            return Result.fail(r==1?"库存不足":"不能重复下单");
        }
        VoucherOrder voucherOrder = new VoucherOrder();
//        设置订单ID

        voucherOrder.setId(order);
//        设置用户ID
        voucherOrder.setUserId(id);
//        设置VoucherID
        voucherOrder.setVoucherId(voucherId);
        orderTasks.add(voucherOrder);
        proxy = (IVoucherOrderService) AopContext.currentProxy();

        return Result.ok(order);
    }

//    @Override
//    @Transactional
//    public Result seckillVoucher(Long voucherId) {
////          查询优惠券
//        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
////        判断秒杀是否开始
//        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
//            return Result.fail("秒杀尚未开始");
//        }
//        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
//            return Result.fail("秒杀已经结束");
//        }
//        if (voucher.getStock() < 1) {
//            return Result.fail("库存不足！");
//        }
//        Long id1 = UserHolder.getUser().getId();
//        RLock lock = redissonClient.getLock("order:" + id1);
//        boolean b = lock.tryLock();
//        if(!b){
//           return Result.fail("不允许重复下单！");
//        }
//        try{
//            IVoucherOrderService o = (IVoucherOrderService) AopContext.currentProxy();
//            return o.createVoucherOrder(voucherId);
//        }finally {
//            lock.unlock();
//        }
//    }

    @Override
    @Transactional
    public Result createVoucherOrder(Long voucherId) {
        Long id1 = UserHolder.getUser().getId();
        int count = query().eq("user_id", id1).eq("voucher_id", voucherId).count();
        if (count > 0) {
            return Result.fail("用户已经购买过了！");
        }
//        创建订单
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock - 1")
                .eq("voucher_id", voucherId)
                .gt("stock", 0)
                .update();
        if (!success) {
            //扣除失败
            return Result.fail("库存不足");
        }
        VoucherOrder voucherOrder = new VoucherOrder();
//        设置订单ID
        long order = redisIdWorker.nextId("order");
        voucherOrder.setId(order);
//        设置用户ID
        long id = UserHolder.getUser().getId();
        voucherOrder.setUserId(id);
//        设置VoucherID
        voucherOrder.setVoucherId(voucherId);
        save(voucherOrder);

        return Result.ok(id);
    }

    @Override
    @Transactional
    public void createVoucherOrder(VoucherOrder voucherOrder) {
        Long id1 = voucherOrder.getUserId();
        int count = query().eq("user_id", id1).eq("voucher_id", voucherOrder.getVoucherId()).count();
        if (count > 0) {
            log.error("用户已经购买过了！");
        }
//        创建订单
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock - 1")
                .eq("voucher_id", voucherOrder.getVoucherId())
                .gt("stock", 0)
                .update();
        if (!success) {
            //扣除失败
            log.error("库存不足");
        }
        save(voucherOrder);
    }
}
